syzbot


general protection fault in start_motor (3)

Status: auto-obsoleted due to no activity on 2024/01/11 01:58
Subsystems: block
[Documentation on labels]
Reported-by: syzbot+1fad709a9a55674f0e0b@syzkaller.appspotmail.com
First crash: 257d, last: 154d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [block?] general protection fault in start_motor (3) 0 (1) 2023/08/14 10:27
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in start_motor block 10 723d 865d 0/26 auto-closed as invalid on 2022/07/11 06:34
upstream general protection fault in start_motor (2) block syz 2 403d 550d 0/26 auto-obsoleted due to no activity on 2023/05/26 20:02
Last patch testing requests (2)
Created Duration User Patch Repo Result
2023/11/12 04:10 39m retest repro upstream OK log
2023/09/03 03:46 15m retest repro upstream report log

Sample crash report:
floppy1: FDC access conflict!
general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 PID: 12 Comm: kworker/u16:1 Not tainted 6.5.0-rc6-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: floppy floppy_work_workfn
RIP: 0010:start_motor+0x3a/0x3e0 drivers/block/floppy.c:1905
Code: 08 e8 da 6d 50 fc 48 8b 1d 73 8c 0d 0d 48 b8 00 00 00 00 00 fc ff df 0f b6 2d c2 76 0d 0d 48 89 da 48 c1 ea 03 89 e9 41 89 ed <0f> b6 04 02 83 e1 03 41 83 e5 03 84 c0 74 08 3c 03 0f 8e a8 02 00
RSP: 0018:ffffc90000317c70 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8534b2e6 RDI: ffffffff8534e840
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff8534e840
R13: 0000000000000001 R14: ffff88801cfc5000 R15: ffffffff8d6dffe0
FS:  0000000000000000(0000) GS:ffff88806b600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2f4f471c98 CR3: 00000000222a8000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 floppy_ready+0x87/0x1b40 drivers/block/floppy.c:1932
 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2600
 worker_thread+0x687/0x1110 kernel/workqueue.c:2751
 kthread+0x33a/0x430 kernel/kthread.c:389
 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:start_motor+0x3a/0x3e0 drivers/block/floppy.c:1905
Code: 08 e8 da 6d 50 fc 48 8b 1d 73 8c 0d 0d 48 b8 00 00 00 00 00 fc ff df 0f b6 2d c2 76 0d 0d 48 89 da 48 c1 ea 03 89 e9 41 89 ed <0f> b6 04 02 83 e1 03 41 83 e5 03 84 c0 74 08 3c 03 0f 8e a8 02 00
RSP: 0018:ffffc90000317c70 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8534b2e6 RDI: ffffffff8534e840
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff8534e840
R13: 0000000000000001 R14: ffff88801cfc5000 R15: ffffffff8d6dffe0
FS:  0000000000000000(0000) GS:ffff88806b600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2f4f471c98 CR3: 00000000222a8000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	08 e8                	or     %ch,%al
   2:	da 6d 50             	fisubrl 0x50(%rbp)
   5:	fc                   	cld
   6:	48 8b 1d 73 8c 0d 0d 	mov    0xd0d8c73(%rip),%rbx        # 0xd0d8c80
   d:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  14:	fc ff df
  17:	0f b6 2d c2 76 0d 0d 	movzbl 0xd0d76c2(%rip),%ebp        # 0xd0d76e0
  1e:	48 89 da             	mov    %rbx,%rdx
  21:	48 c1 ea 03          	shr    $0x3,%rdx
  25:	89 e9                	mov    %ebp,%ecx
  27:	41 89 ed             	mov    %ebp,%r13d
* 2a:	0f b6 04 02          	movzbl (%rdx,%rax,1),%eax <-- trapping instruction
  2e:	83 e1 03             	and    $0x3,%ecx
  31:	41 83 e5 03          	and    $0x3,%r13d
  35:	84 c0                	test   %al,%al
  37:	74 08                	je     0x41
  39:	3c 03                	cmp    $0x3,%al
  3b:	0f                   	.byte 0xf
  3c:	8e                   	.byte 0x8e
  3d:	a8 02                	test   $0x2,%al

Crashes (12):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/08/14 10:27 upstream 2ccdd1b13c59 39990d51 .config console log report syz [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in start_motor
2023/10/03 01:57 upstream ce36c8b14987 65faba36 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in start_motor
2023/09/17 11:04 upstream f0b0d403eabb 0b6a67ac .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in start_motor
2023/09/25 11:31 upstream 6465e260f487 0b6a67ac .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in start_motor
2023/09/24 10:26 upstream 3aba70aed91f 0b6a67ac .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in start_motor
2023/09/20 15:24 upstream 2cf0f7156238 0b6a67ac .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in start_motor
2023/09/18 21:34 upstream ce9ecca0238b 0b6a67ac .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in start_motor
2023/08/20 03:39 upstream 9e6c269de404 d216d8a0 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in start_motor
2023/08/18 00:47 upstream 16931859a650 74b106b6 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in start_motor
2023/08/14 09:07 upstream 2ccdd1b13c59 39990d51 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in start_motor
2023/07/07 04:48 upstream a452483508d7 22ae5830 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in start_motor
2023/06/21 18:13 upstream e660abd551f1 79782afc .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in start_motor
* Struck through repros no longer work on HEAD.